Dental flask



Patented Nom 6, 1923.,

waarin Bilans, or nsroian, New YORK.

:DENTAL russia.

appliaton ala Aiirii s,

Be it vknowny that MARTIN F. BURNS, a'

citizen ot the' United "States,V and af resident v' of Astoria, county ofAv Queens, and Stateot New York,"have invented certain lnevv and useful7 Improvements in DentalFlasls, of which'the followil'ig is a specication". v

This invention relates to, dental apparatus and more'particularlyto dental flasks ot the il@ type]A used; by dentists,l in'V casting' plates,-

bridges,l inlays and; other restorations'.

In casting a plate, bridge or other restoration'adentistfirstmakes aV pattern in wax" ofthe article to be cast. The pattern is then it invested` in an initially plastic and quick hardeningv` composition. Nhen the investment isd'ryy or has'setthevvaX is melted' out ofotherwise" dissipated, andthe cavity-is aired with moire-n maar Thecastn's 'iS the t@ allowed to' cool a'ndispreferably cooled slowly' tofprevent' warping or distor`tion`. When warping ordistortion takes lplace it `k is necessary to swage the casting to its" properkr sh'apf` y y A v lt is verydesirablevl that therate of heat'- ing or coolingtheinvestmen't vand 'the parts containedther'eby be regulated, as "different classes ofwork require diiiere'nt treatment.

vThis invent-ion has foriits object, therefore; toprovide means inapparatus of 'the class described for regulatingthe heating or cooling ot the investment and parts con tained thereby;

Another object oftheinvention is to'provide a' constructionby means of which they quantity/Of investment'used will'be conserved. Y 4

Another object of the'invention is to' provide an investment holder so constructed 40 that the jinvestinent will be'cofnined` therein and will not"enga`g'e'the walls oitithev receptacle. y

Further'objects ot' the invention will' appear from the following description'y taken in connection with the drawings which `'liorm apart oithis application and in which- Fig. 1 isl a view showing'half -in section and halt )in lelevation dental' apparatus constructed in 'accordance with' the invent-ion.`

Fig. 1 and Ashowing the Vconstructionhalt in section and half in elevation.

Fig: 2 isa view .taken Vat lright"angles' to" 1922'.Uv sriai no; safaev.

Fig.. Bisa View Asimilar toy Figfl' but showing another form of the inves'ti'nel'itl holder and , F 4 vis aibroken'sectionl taken substantlally on line 'lfi-eojf yFig. 3, K

rl`he invention be briefly described as including' a receptacle and an investment holder so relativelyl constructed and arranged ythatthe parts maybe adjustedto regulatethe admission of air or heat to the spaces at the sides of theinvestment holder. lzlore particularly described,I the vinvestment holder comprises spaced plates connected throughout'their lengtlrto conline thefinvestment tothe space therebetween( These plates arel so arranged relatively'to the receptacle'that spaces 'are formed between the plates and the wall ofthe receptacle.v ln another form of they invention, namely, that shown in`Figs. 3 and L1,',the space between the platesis contracted toward the' lower ends thereof thereby still further conserving the investment material. y

Referringto the drawings and'particularly to the form of 'the invention shown in' Figs. 1 and 2, the receptacle 10 hasi'a cylin-j drical wall, an"openupper end 11`anda bottom 12 having an opening 13 therethrough. The opening 13 is oblong in shape as clearly lillustrated iinFig. 2. The wall of'4 Theinvestment holder comprisesa pair or" substantially vertical, parallel', imperforate plates lahaving their side edges 4closed in by connecting portions 15 extending substantially throughout` the length of the walls. rlhe porti'ons'l continethe investment to the space between the walls and prevent the engagement of theinvestmenthvith the cylindricalwall 'of the receptacle.

As clearly illustrated in Fig. 2 the distance between the walls 14E is less than the maxi'- mum dimension of the oblong opening 13 inthe bottom 12 of the receptacle and therefore the relative positions ot the investment holder'and the receptacle and bottom 12 thereor1 will determine the size of the openings to the spaces 16 formed between the sides ot the investment holder and the Wall of the receptacle. By relatively rotating these parts, namely, the investment holder' and the receptacle, the openings can bey enlarged or contracted and thereby the admission of air or heat orif desired of a yfiame to the spaces can 'be controlled in a manner to obtain the desired heating or cooling effect.-

Flanges 17 are formed on the Vupper ends of the plates or Walls 14 of the investment holder and extend outwardly therefrom, the

'has formedtherein 4a l'central opening 19`and an outwardlyA extending cylindrical flange i 20 forming avvall for the opening. Countersunk apertures 21 are `formed inthe cover 18 and are adapted to receive investment: that is forced out therethrough 'thereby7 securing the cover of the receptacle. i V

this case be filled before .being placed lwithin the receptacle 10 since thespace Within the investment holder is enclosed by the .vvallslfi and 15.

In order to obtain a slower cooling eiect I have provided 'a cap 22 having a packing or lining 23 forV the lower end of the receptacle and a cap'24 having apacking or lin ing 25 for the opening 19 of the cover plate 18, this capbeing adapted to fit over the cylindrical flange 20.4 l

The construction. shown in Figs. 3 anda is similar to that shown in Figs. 1 and 2v f detractfrom .the proper functioning ofthe investment holder. As Vshown in Fig. 3 the investmentholder is provided lat its lovver end with laterally and outwardly extendingy flanges 81 formed at the ends of the holder and in alinement With the connectingporthejinvestment holder and theinvestment is then filled in to entirely enclose the pattern. The Wax is then dissipatedby heaty andthe cavity left Yby the'WaX. is filled in With molten metal. AThe investmentv holder `and the receptacle canjbe'so relatively ad-.g

j usted as to give the desired heating or cooling Vefi'ectsby rotating'the holder and recep tacle with respect to eachother. This relative rotation Yof the ,parts may be more?V readily 'accomplished byV the construction above described sincethe end Walls 15 con'- fine the investment andprevent--it .from en- A gaging the Wall of the'receptacle. Ther-ate.

of cooling may also be regulatedl'by using the caps 22l and 24since these caps Will confine the air vvithin the apparatus and Will thereby effect a much slower rate of cooling. Although certain specific embodiments of the invention have been illustrated andl described, it will be understood that the invention is capable of further modification and that further `cluinges in the construction and in the arrangement ofthe various cooperating parts may be made WithoutV de- Atending -throughfthe length of said Walls,

said investment holder havingflang'es eX- tending laterallygand outwardly from one end thereof, shaped to fit the innerl Walll of the,receptacle.` Y r 2. In combination7 a receptacle having an imper-foratecylindrical Wall, an investment- Walls and A'connectingV portions extending throughout the length of said Walls, and

the receptacle Wall.

3. `In combination, a'recepftacle having an; Y imperforate cylindricalvvall, anv investmentV holder having substantially vertical, spaced Walls and connecting portionsV extending throughout the length of said vvalls, and

curved inl section for at least V'a portion 'of their length to fit the'inn'er surfaceI ofth'e receptacle Wall. i

4. In combination, a receptacle, an investment holder having a pair? of straight y holderv having substantially vertical,YV spaced Y i The investment holder. may if desired inY curved in section to fit the inner surface of flat sides spaced from each other` and from` the:V receptacle Wall `and having ends curved to fit the receptacle Wall and connecting saidV sidesthroughout their length.

5. In combination, a receptacle having' 'an apertured bottom, an'v investment; holder having a pair of straight Yfiat''sides'spaced from each other and from the receptacle".

Wall and havingends connecting saidfside's throughout their length, fthe distance 'be- I tvveen the" spaced sidesof the holder being less than the maximum dimension opening in the receptacle bottom.

` 6. In combination, a receptacle,",an invest.-

ment 'holder having Vpair of straight, flatA sides spaced from each otherand from the receptacle Wall and having lendsv connecting said sides throughout their length, the sides being narrower at their lowerends than at, the yupper ends.

7. In combination,

flanges extending outwardly from theupperA ends lof the holder sides.

8. An investment holder having alpai-1iofV la receptacle, an invest-'iVV .i ment holder having a pair. of straight, fiat sides Vspaced from'each other andV from the 125 parallel plates, curved connecting walls being laterally from said connecting walls, tween said plates and segmental flanges exsaid anges conforming in curvature to the tending laterally from saicl connecting walls. inner surface of the receptacle. 10 9. In combination, a receptacle, an invest- In witness whereof, I have hereunto set ment holder therein having a pair of paralmy hand this 22d day of March, 1922.

lel plates7 curved connecting walls between said plates and segmental flanges eXtend- MARTIN F. BURNS. 

